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<pre><span class="comment"> /****************************************************************************
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 ** Copyright (C) 2004-2008 Trolltech ASA. All rights reserved.
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 #include &lt;QtGui&gt;

 #include &quot;mainwindow.h&quot;

 MainWindow::MainWindow()
 {
     setAttribute(Qt::WA_DeleteOnClose);

     textEdit = new QTextEdit;
     setCentralWidget(textEdit);

     createActions();
     createMenus();
     (void)statusBar();

     setWindowTitle(tr(&quot;Recent Files&quot;));
     resize(400, 300);
 }

 void MainWindow::newFile()
 {
     MainWindow *other = new MainWindow;
     other-&gt;show();
 }

 void MainWindow::open()
 {
     QString fileName = QFileDialog::getOpenFileName(this);
     if (!fileName.isEmpty())
         loadFile(fileName);
 }

 void MainWindow::save()
 {
     if (curFile.isEmpty())
         saveAs();
     else
         saveFile(curFile);
 }

 void MainWindow::saveAs()
 {
     QString fileName = QFileDialog::getSaveFileName(this);
     if (fileName.isEmpty())
         return;

     saveFile(fileName);
 }

 void MainWindow::openRecentFile()
 {
     QAction *action = qobject_cast&lt;QAction *&gt;(sender());
     if (action)
         loadFile(action-&gt;data().toString());
 }

 void MainWindow::about()
 {
    QMessageBox::about(this, tr(&quot;About Recent Files&quot;),
             tr(&quot;The &lt;b&gt;Recent Files&lt;/b&gt; example demonstrates how to provide a &quot;
                &quot;recently used file menu in a Qt application.&quot;));
 }

 void MainWindow::createActions()
 {
     newAct = new QAction(tr(&quot;&amp;New&quot;), this);
     newAct-&gt;setShortcut(tr(&quot;Ctrl+N&quot;));
     newAct-&gt;setStatusTip(tr(&quot;Create a new file&quot;));
     connect(newAct, SIGNAL(triggered()), this, SLOT(newFile()));

     openAct = new QAction(tr(&quot;&amp;Open...&quot;), this);
     openAct-&gt;setShortcut(tr(&quot;Ctrl+O&quot;));
     openAct-&gt;setStatusTip(tr(&quot;Open an existing file&quot;));
     connect(openAct, SIGNAL(triggered()), this, SLOT(open()));

     saveAct = new QAction(tr(&quot;&amp;Save&quot;), this);
     saveAct-&gt;setShortcut(tr(&quot;Ctrl+S&quot;));
     saveAct-&gt;setStatusTip(tr(&quot;Save the document to disk&quot;));
     connect(saveAct, SIGNAL(triggered()), this, SLOT(save()));

     saveAsAct = new QAction(tr(&quot;Save &amp;As...&quot;), this);
     saveAsAct-&gt;setStatusTip(tr(&quot;Save the document under a new name&quot;));
     connect(saveAsAct, SIGNAL(triggered()), this, SLOT(saveAs()));

     for (int i = 0; i &lt; MaxRecentFiles; ++i) {
         recentFileActs[i] = new QAction(this);
         recentFileActs[i]-&gt;setVisible(false);
         connect(recentFileActs[i], SIGNAL(triggered()),
                 this, SLOT(openRecentFile()));
     }

     exitAct = new QAction(tr(&quot;E&amp;xit&quot;), this);
     exitAct-&gt;setShortcut(tr(&quot;Ctrl+Q&quot;));
     exitAct-&gt;setStatusTip(tr(&quot;Exit the application&quot;));
     connect(exitAct, SIGNAL(triggered()), qApp, SLOT(closeAllWindows()));

     aboutAct = new QAction(tr(&quot;&amp;About&quot;), this);
     aboutAct-&gt;setStatusTip(tr(&quot;Show the application's About box&quot;));
     connect(aboutAct, SIGNAL(triggered()), this, SLOT(about()));

     aboutQtAct = new QAction(tr(&quot;About &amp;Qt&quot;), this);
     aboutQtAct-&gt;setStatusTip(tr(&quot;Show the Qt library's About box&quot;));
     connect(aboutQtAct, SIGNAL(triggered()), qApp, SLOT(aboutQt()));
 }

 void MainWindow::createMenus()
 {
     fileMenu = menuBar()-&gt;addMenu(tr(&quot;&amp;File&quot;));
     fileMenu-&gt;addAction(newAct);
     fileMenu-&gt;addAction(openAct);
     fileMenu-&gt;addAction(saveAct);
     fileMenu-&gt;addAction(saveAsAct);
     separatorAct = fileMenu-&gt;addSeparator();
     for (int i = 0; i &lt; MaxRecentFiles; ++i)
         fileMenu-&gt;addAction(recentFileActs[i]);
     fileMenu-&gt;addSeparator();
     fileMenu-&gt;addAction(exitAct);
     updateRecentFileActions();

     menuBar()-&gt;addSeparator();

     helpMenu = menuBar()-&gt;addMenu(tr(&quot;&amp;Help&quot;));
     helpMenu-&gt;addAction(aboutAct);
     helpMenu-&gt;addAction(aboutQtAct);
 }

 void MainWindow::loadFile(const QString &amp;fileName)
 {
     QFile file(fileName);
     if (!file.open(QFile::ReadOnly | QFile::Text)) {
         QMessageBox::warning(this, tr(&quot;Recent Files&quot;),
                              tr(&quot;Cannot read file %1:\n%2.&quot;)
                              .arg(fileName)
                              .arg(file.errorString()));
         return;
     }

     QTextStream in(&amp;file);
     QApplication::setOverrideCursor(Qt::WaitCursor);
     textEdit-&gt;setPlainText(in.readAll());
     QApplication::restoreOverrideCursor();

     setCurrentFile(fileName);
     statusBar()-&gt;showMessage(tr(&quot;File loaded&quot;), 2000);
 }

 void MainWindow::saveFile(const QString &amp;fileName)
 {
     QFile file(fileName);
     if (!file.open(QFile::WriteOnly | QFile::Text)) {
         QMessageBox::warning(this, tr(&quot;Recent Files&quot;),
                              tr(&quot;Cannot write file %1:\n%2.&quot;)
                              .arg(fileName)
                              .arg(file.errorString()));
         return;
     }

     QTextStream out(&amp;file);
     QApplication::setOverrideCursor(Qt::WaitCursor);
     out &lt;&lt; textEdit-&gt;toPlainText();
     QApplication::restoreOverrideCursor();

     setCurrentFile(fileName);
     statusBar()-&gt;showMessage(tr(&quot;File saved&quot;), 2000);
 }

 void MainWindow::setCurrentFile(const QString &amp;fileName)
 {
     curFile = fileName;
     if (curFile.isEmpty())
         setWindowTitle(tr(&quot;Recent Files&quot;));
     else
         setWindowTitle(tr(&quot;%1 - %2&quot;).arg(strippedName(curFile))
                                     .arg(tr(&quot;Recent Files&quot;)));

     QSettings settings(&quot;Trolltech&quot;, &quot;Recent Files Example&quot;);
     QStringList files = settings.value(&quot;recentFileList&quot;).toStringList();
     files.removeAll(fileName);
     files.prepend(fileName);
     while (files.size() &gt; MaxRecentFiles)
         files.removeLast();

     settings.setValue(&quot;recentFileList&quot;, files);

     foreach (QWidget *widget, QApplication::topLevelWidgets()) {
         MainWindow *mainWin = qobject_cast&lt;MainWindow *&gt;(widget);
         if (mainWin)
             mainWin-&gt;updateRecentFileActions();
     }
 }

 void MainWindow::updateRecentFileActions()
 {
     QSettings settings(&quot;Trolltech&quot;, &quot;Recent Files Example&quot;);
     QStringList files = settings.value(&quot;recentFileList&quot;).toStringList();

     int numRecentFiles = qMin(files.size(), (int)MaxRecentFiles);

     for (int i = 0; i &lt; numRecentFiles; ++i) {
         QString text = tr(&quot;&amp;%1 %2&quot;).arg(i + 1).arg(strippedName(files[i]));
         recentFileActs[i]-&gt;setText(text);
         recentFileActs[i]-&gt;setData(files[i]);
         recentFileActs[i]-&gt;setVisible(true);
     }
     for (int j = numRecentFiles; j &lt; MaxRecentFiles; ++j)
         recentFileActs[j]-&gt;setVisible(false);

     separatorAct-&gt;setVisible(numRecentFiles &gt; 0);
 }

 QString MainWindow::strippedName(const QString &amp;fullFileName)
 {
     return QFileInfo(fullFileName).fileName();
 }</pre>
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